Variable expansion frame system for deploying medical devices and methods of use

ABSTRACT

An expansion frame system for deploying medical devices in a patient&#39;s body cavity. The system typically includes an inner wire disposed within a lumen of an outer wire. Distal ends of the inner and outer wires are attached to a substantially circular frame at first and second points. During use, the outer wire is displaced relative to the inner wire, causing the circular frame to rotate about an axis perpendicular to the line defined by the first and second points. Medical devices, such as a filter, a stent, an occluder or a manometer, can be mounted on the circular frame. The diameter of the expansion frame can be varied to achieve optimal contact with the luminal wall of the body cavity. Methods of using the expansion frame system for temporary or permanent placement of a medical device is disclosed.

FIELD OF THE INVENTION

The present invention relates generally to systems and methods usefulfor deploying medical devices within a body, such as a patient's bloodvessel. More specifically, the invention provides a variable diameterexpansion frame system for temporary or permanent deployment of medicaldevices, such as a blood filter, a stent, a manometer, or an occluder,in arteries or veins. The frame can be placed in a collapsed conditionto facilitate insertion of the device and in an expanded condition todeploy the medical device. The diameter of the frame can be varied toachieve maximal contact with the vascular wall.

BACKGROUND OF THE INVENTION

Treatment of thrombotic or atherosclerotic lesions in blood vesselsusing the endovascular approach has recently been proven to be aneffective and reliable alternative to surgical intervention in selectedpatients. For example, directional atherectomy and percutaneoustranslumenal coronary angioplasty (PTCA) with or without stentdeployment are useful in treating patients with coronary occlusion.These endovascular techniques have also proven useful in treating othervascular lesions in, for example, carotid artery stenosis, peripheralarterial occlusive disease (especially the aorta, the iliac artery, andthe femoral artery), renal artery stenosis caused by atherosclerosis orfibromuscular disease, superior vena cava syndrome, and occlusion iliacvein thrombosis resistant to thrombolysis.

It is well recognized that one of the complications associated withendovascular techniques is the dislodgment of embolic materials whichcan occur during manipulation of the vessel, thereby causing occlusionof the narrower vessels downstream and ischemia or infarct of the organwhich the vessel supplies. There are a number of devices designed toprovide blood filtering for entrapment of vascular emboli in arteries.These devices have also been placed prophylactically, e.g., in theinferior vena cava, for prevention of pulmonary embolism in patientswith a propensity for thromboembolism.

Filters mounted to the distal end of guidewires have been proposed forintravascular blood filtration. A majority of these devices includes afilter which is attached to a guidewire and is mechanically actuated viastruts or a pre-shaped basket which deploys in the vessel. These filtersare typically mesh “parachutes” which are attached to the shaft of thewire at the distal end and to wire struts which extend outward in aradial direction on the proximal end. The radial struts open theproximal end of the filter to the wall of the vessel. Blood flowingthrough the vessel is forced through the mesh thereby capturing embolicmaterial in the filter.

One of the major disadvantages of present filtering devices is that themaximal expansion diameters of the deployed filters are fixed andsometimes fail to optimally and uniformly engage the vascular wall. Anoperator can only estimate the diameter of the vessel of interest andchoose the filter accordingly. If the vessel, e.g., the aorta, issignificantly affected by atherosclosis, the actual luminal diameter ofthe vessel would be over-estimated. In addition to blood filteringdevices, this problem is also recognized for deployment of other medicaldevices, e.g., stents and occluders.

What is needed are simple and safe devices which facilitate placement ofother medical devices in a body cavity, such as arteries and veins, andcan be variably adjusted to ensure optimal placement of the medicaldevices. Existing devices are inadequate for this purpose.

SUMMARY OF THE INVENTION

The present invention provides devices and methods for temporaryplacement of medical devices, including a filter, an occluder, and astent in a body cavity. More specifically, the invention provides aexpansion frame system, the diameter of which can be variably adjustedto facilitates, for example, insertion of blood filter for capturingembolic material in an artery or vein.

In one embodiment, the expansion frame system includes an outer wire, aninner wire, and a circular or elliptical frame. The outer wire has alumen communicating with a proximal end and a distal end, and is adaptedto receive a percutaneous endovascular medical instrument. The innerwire, having a proximal end and a distal end, is disposed within thelumen of the outer wire. The distal ends of the inner and outer wiresare attached, respectively, to the frame at first and secondcircumferential points at approximately 180° from each other. Theproximal ends of the inner and outer wires can be manipulated so thatthe outer wire can be displaced relative to the inner wire, causing theframe to rotate about an axis perpendicular to the line defined by thefirst and second circumferential points. In this way, the frame can beplaced in a collapsed or an expanded condition.

In another embodiment, the expansion frame system further includes aforce biasing element, such as a spring, disposed about the distal endof the inner wire. The distal region of the outer wire has an opening,through which the inner wire passes to attach to the circular orelliptical frame. The biasing element is capable of biasing the secondcircumferential point of the circular frame away from the opening of theouter wire.

In still another embodiment, the expansion frame system includes asyringe having a barrel and a plunger, where the outer wire is housedwithin a lumen of the barrel and is mounted on a distal surface of theplunger. The proximal end of the inner wire passes through the distalsurface of the plunger and is mounted on the barrel. When the plunger isadvanced slideably in the lumen of the barrel, the outer wire isdisplaced relative to the inner wire, causing the frame to rotate aboutan axis perpendicular to the line defined by the first and secondcircumferential points. In other embodiments, the proximal end of thebarrel includes a locking mechanism, capable of fixing the displacementof the plunger relative to the barrel.

In certain embodiments, an occluding device, such as a non-permeablemembrane, is mounted on the frame. When in use, the membrane providesisolation of blood flow in a vessel, e.g., isolation of aortic bloodflow during cardiopulmonary bypass. In other embodiments, a filteringdevice, e.g., a parachute, basket, or scroll, is mounted on the frame,and a mesh is disposed over the frame. The filtering device may includean inflation seal for achieving better contact with the vascular walls.The construction and use of an associated filter mesh have beenthoroughly discussed in earlier applications including Barbut et al.,U.S. application Ser. No. 08/533,137, filed Nov. 7, 1995, Barbut et al.,U.S. application Ser. No. 08/580,223, filed Dec. 28, 1995, Barbut etal., U.S. application Ser. No. 08/584,759, filed Jan. 9, 1996, Barbut etal., U.S. application Ser. No. 08/640,015, filed Apr. 30 1996, Barbut etal., U.S. application Ser. No. 08/645,762, filed May 14, 1996, and,Barbut et al., U.S. Pat. No. 5,662,671, and the contents of each ofthese prior applications are expressly incorporated herein by reference.

The methods of the present invention are useful for deploying a medicaldevice within a body cavity for, e.g., protecting a patient fromembolization during an endovascular procedure. The expansion framesystem can be inserted to capture plaque and/or thrombi from thecoronary artery, aorta, common carotid artery, external and internalcarotid arteries, brachiocephalic trunk, middle cerebral artery, basilarartery, subclavian artery, brachial artery, axillary artery, iliacartery, renal artery, femoral artery, popliteal artery, celiac artery,superior mesenteric artery, inferior mesenteric artery, anterior tibialartery, posterior tibial artery, and all other arteries carryingoxygenated blood. The expansion frame system can be usedprophylactically in patients with hypercoagulable state, includingprotein C or protein S deficiency, to prevent pulmonary embolism. It canalso be used during an endovascular procedure to prevent distalembolization of thrombi and/or foreign bodies in the venous circulation,including the superior vena cava, inferior vena cava, external andinternal jugular veins, brachiocephalic vein, pulmonary artery,subclavian vein, brachial vein, axillary vein, iliac vein, renal vein,femoral vein, profunda femoris vein, great saphenous vein, portal vein,splenic vein, hepatic vein, and azygous vein.

In a first method of using the expansion frame system, the frame, in acollapsed condition, is inserted percutaneously or through an incisioninto a patient's body cavity, and is advanced into a region of interest.The proximal end of the outer wire is retracted relative to the proximalend of the inner wire, causing the frame to rotate about an axisperpendicular to the line defined by the first and second points,thereby increasing its profile. In this way, the frame circumferentiallyengages the luminal wall.

When used during an endovascular procedure, e.g., percutaneoustransluminal angioplasty of a coronary or carotid artery, to provideprotection against distal embolization, the expansion frame system,having a filter mounted on the frame in a collapsed condition, isinserted through a peripheral artery into the coronary or carotid arterydistal to the occluding lesion. In using the embodiments which include asyringe, the plunger is depressed distally against the barrel, therebyretracting the proximal end of the outer wire relative to the innerwire, and placing the frame in a collapsed condition. After the frame ispositioned downstream from the occluding lesion, the plunger isreleased, moving proximally within the barrel of the syringe, therebydistancing the proximal end of the outer wire relative to the innerwire, and placing the frame in an expanded condition. The contactbetween the circumference of the frame and the luminal wall of theartery is variably adjusted to obtain optimal contact.

The angioplasty catheter carrying the angioplasty balloon at a distalend is inserted into the artery, over the outer wire in certainembodiments, and the balloon is inflated to dilate the stenotic vascularlumen. Embolic debris generated during the angioplasty procedure arecaptured by the filter mounted on the expansion frame. After adequateluminal diameter is re-established for coronary blood flow, theexpansion frame with the entrapped emboli is collapsed by depressing theplunger against the barrel of the syringe, and removed from the artery.

It will be understood that there are several advantages in using thevariable diameter expansion frame disclosed herein for deploying amedical device. For example, the expansion frame system (1) can be usedto deploy a variety of medical devices, including a filter, stent, andan occluder, (2) can withstand high arterial blood flow for an extendedtime, (3) can be used to deploy a variety of blood filters, particularlysuited for temporary filtration of blood in any vessel to entrap embolicdebris, thereby minimizing neurologic, cognitive, and cardiaccomplications associated with distal embolization, (4) can be used withany endovascular catheter with or without an imaging device, (5) can beinserted into vessels or a body cavity of various diameter, (6) can bevariably adjusted to achieve optimal contact between the frame and theinner wall of a vessel or body cavity, and (7) can be used in adult andpediatric patients.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A depicts an embodiment of an expansion frame system including asyringe according to the present invention.

FIG. 1B depicts the expansion frame system of FIG. 1A having a frame ina collapsed condition.

FIG. 1C depicts the expansion frame system of FIG. 1A showing themechanism within tubular member 49.

FIG. 2A depicts the expansion frame system of FIG. 1B carrying a filterin a collapsed condition inserted in a vessel.

FIG. 2B depicts the expansion frame system of FIG. 2A deploying thefilter in a vessel.

FIG. 2C depicts the expansion frame system of FIG. 2A deploying thefilter in another vessel having a smaller diameter.

FIG. 2D depicts a distal view of the expansion frame system of FIG. 2C.

FIG. 3A depicts the expansion frame system of FIG. 1B carrying amembrane inserted in a vessel.

FIG. 3B depicts the expansion frame system of FIG. 3A deploying themembrane in the vessel.

FIG. 4 depicts an expansion frame system carrying a filter deployed inthe aorta through a side port of a cannula.

DETAILED DESCRIPTION

Although the variable expansion frame system is most useful in deployingblood filters in a patient's blood vessel as disclosed herein, it willbe understood that the system can also be used to deploy a variety ofother medical devices, e.g., a stent, an occluder, an endoscopic imagingdevice, or a manometer, in various body cavities.

In a first embodiment, the expansion frame system includes inner wire10, outer wire 20, syringe 30, and substantially circular frame 40 asdepicted in FIGS. 1A and 1B. Outer wire 20 has proximal end 21, distalend 22 and lumen 25. Inner wire 10, having proximal end 11 and distalend 12, is disposed within lumen 25 of the outer wire. Distal end 12 ofthe inner wire and distal end 22 of the outer wire are attached,respectively, to frame 40 at circumferential point 41 andcircumferential point 42. The frame is substantially circular orelliptical. Point 41 is disposed approximately 180° from point 42. Incertain embodiments, point 41 is disposed approximately 30°, 45°, 60°,90°, 120°, 135°, or any other suitable angles from point 42. Distalregion 23 of outer wire 20 has an opening 70 (FIG. 1C) through its wall,which is enclosed in tubular member 49 and allows inner wire 10 to passthrough. Spring 45, a force biasing element, is disposed about distalend 12 of inner wire 10, thereby biasing point 41 away from the openingof the outer wire. Syringe 30 comprises plunger 31 slideably inserted inlumen 33 of barrel 32. Proximal end 21 of outer wire 20 is mounted ondistal surface 35 of the plunger. Proximal end 11 of inner wire 10passes through distal surface 35 of the plunger and is mounted onattachment 36 of the barrel.

In use, as depicted in FIG. 1B, frame 40 is collapsed by advancingplunger 31 distally relative to barrel 32, thereby retracting proximalend 21 of the outer wire relative to proximal end 11 of the inner wire,and causing frame 40 to rotate about an axis perpendicular to the linedefined by points 41 and 42. Medical devices mounted or carried on frame40 are placed in a collapsed condition to facilitate insertion into abody cavity. The displacement between plunger 31 and barrel 32 may befixed by a locking mechanism included in a proximal end of the syringe.When frame 40 is positioned in the region of interest, plunger 31 iswithdrawn, thereby placing frame 40 in an expanded condition anddeploying the medical device. The diameter of the substantially circularframe can be varied by adjusting the displacement between the proximalend of the outer wire relative to the inner wire. In certainembodiments, a radiopaque marker may be mounted on frame 40, tubularmember 49, or distal regions of the inner and/or the outer wire forverifying the position of the deployed device.

The expansion frame system of FIG. 1B is inserted in an artery distal toatheromatous occlusion 100 as depicted in FIG. 2A. A filter, having mesh50 is mounted on frame 40. The frame is placed in a collapsed conditionto facilitate insertion through the stenotic vascular lesion. In FIG.2B, when the filter is positioned downstream from occlusion 100, frame40 is rotated by retracting the proximal end of outer wire 20 relativeto inner wire 10, thereby circumferentially engaging the luminal walland expanding the filter in the artery. The diameter of frame 40 can bevaried by adjusting the displacement between a proximal end of the outerwire relative to the inner wire to maximally engage the frame with thevascular wall. Endoscopic procedures, including atherectomy,angioplasty, and/or stenting, can be performed on the occlusion. Embolicmaterials, such as calcium, atheromatous plaque, tissue debris, and/orthrombi, are captured by mesh 50 of the filter. After adequate luminalsize is achieved after the procedures, blood flow is re-established topush the embolic material toward mesh 50 and to perfuse distal organs.After completion of the procedure, the endovascular device is withdrawn.Frame 40 and the filter with the captured embolic debris are collapsedand removed from the vessel.

In situations where the luminal diameter of the vessel is overestimated,i.e., the diameter of the frame exceeding the luminal diameter, frame 40can be adjusted to achieve maximal contact with the vessel wall asdepicted in FIG. 2C. FIG. 2D depicts a distal view of frame 40 with mesh50.

By way of example, when the filter as disclosed herein is intended foruse in the aorta, the area of the mesh required for the device iscalculated from Bemoulli's equation as described in our earlierapplications including Barbut et al., U.S. application Serial No., U.S.application Serial No. 08/553,137, filed Nov. 7, 1995, Barbut et al.,U.S. application Serial No. 08/580,223, filed Dec. 28, 1995, Barbut etal., U.S. application Ser. No. 08/584,759, filed Jan. 9, 1996, Barbut etal., U.S. application Ser. No. 08/640,015, filed Apr. 30, 1996, andBarbut et al., and U.S. application Ser. No. 08/645,762, filed May 14,1996.

In an embodiment of the filter that is to be used in the aorta, meshwith dimensions within the following ranges is desirable: mesh area is0.004-5 in², more preferably 0.007-4 in², more preferably 0.010-3 in²,more preferably 0.015-2 in², more preferably 0.020-1 in², morepreferably 0.025-0.076 in²; mesh thickness is 60-280 μm, more preferably70-270 μm, more preferably 80-260 μm, more preferably 90-250 μm, morepreferably 100-250 μm, more preferably 120-230 μm, more preferably140-210 μm; thread diameter is 30-145 μm, more preferably 40-135 μm,more preferably 50-125 μm, more preferably 60-115 μm, more preferably70-105 μm, and pore size is 500 μm or less, more preferably 400 μm orless, more preferably 300 μm or less, more preferably 200 μm or less,more preferably 100 μm or less, more preferably 50 μm or less andusually larger than at least a red blood cell. In a preferred embodimentof the invention, mesh area is 2-8 in², mesh thickness is 60-200 μm,thread diameter is 30-100 μm, and pore size is 50-300 μm. In a furtherpreferred embodiment of the invention, mesh area is 3-5 in², meshthickness is 60-150 μm, thread diameter is 50-80 μm, and pore size is100-250 μm.

Once appropriate physical characteristics are determined, suitable meshcan be found among standard meshes known in the art. For example,polyester meshes may be used, such as meshes made by Saati Corporationsand Tetko Inc. These are available in sheet form and can be easily cutand formed into a desired shape. In a preferred embodiment, the mesh issonic welded or adhesive bonded into a cone shape. Other meshes known inthe art, which have the desired physical characteristics, are alsosuitable. Anticoagulants, such as heparin and heparinoids, may beapplied to the mesh to reduce the chances of blood clotting on the mesh.Anticoagulants other than heparinoids also may be used, e.g., monoclonalantibodies such as ReoPro (Centocor). The anticoagulant may be paintedor sprayed onto the mesh. A chemical dip comprising the anticoagulantalso may be used. Other methods known in the art for applying chemicalsto mesh may be used.

The expansion frame system can be used to deploy other devices, such asnon-permeable membrane 60, as depicted in FIGS. 3A and 3B. In FIG. 3A,membrane 60 is mounted on frame 40, which is placed in a collapsedcondition by retracting a proximal end of outer wire 20 relative toinner wire 10. When the membrane is positioned within a region ofinterest in a vessel, frame is rotated to circumferentially engage theluminal wall. When deployed in the ascending aorta duringcardiopulmonary bypass, the nonpermeable membrane provides circulatoryisolation of the coronary blood flow from the peripheral vascularsystem.

In other embodiments, the expansion frame system can be used to deploy afilter or any other device directly into the aorta through a cannulahaving a side port as described in Maahs, U.S. Pat. No. 5,846,260,incorporated herein by reference in its entirety. In FIG. 4, theexpansion frame system carrying a filter having mesh 50 is insertedthrough side port 202 of cannula 200. Cannula 200 includes lumen 205which communicates with perfusion port 201. The lumen communicating withside port 202 may communicate with lumen 205, or in other embodimentsremains separate and isolated from lumen 205. When the cannula isinserted into aorta 150 during cardiopulmonary bypass, for example, port201 is positioned downstream in the aorta to perfuse peripheral organs.The filter is deployed upstream in the aorta through port 203 of thecannula to capture any embolic material generated during cardiothoracicprocedures. In still other embodiments, the expansion frame system canbe used through any vascular introducer, such as those described inMartinez et al., U.S. application Ser. No. 09/365,650, entitled MODULARACCESS PORT FOR DEVICE DELIVERY, filed Aug. 2, 1999, incorporated hereinby reference in its entirety.

The length of the inner and outer wire will generally be between 30 and300 centimeters, preferably approximately between 50 and 180centimeters. The inner diameter of the lumen of the outer wire willgenerally be between 0.05 and 0.5 centimeters, preferably approximatelybetween 0.1 and 0.25 centimeters. The diameter of the expansion framewill be capable of expansion to an outer diameter of at least 0.3 cm,more preferably at least 1.5 cm, more preferably at least 2 cm, morepreferably at least 2.5 cm, more preferably at least 3 cm, morepreferably at least 3.5 cm, more preferably at least 4 cm, morepreferably at least 4.5 cm, more preferably at least 5 cm, morepreferably at least 5.5 cm, more preferably at least 6 cm. These rangescover suitable diameters for both pediatric use and adult use. Theforegoing ranges are set forth solely for the purpose of illustratingtypical device dimensions. The actual dimensions of a device constructedaccording to the principles of the present invention may obviously varyoutside of the listed ranges without departing from those basicprinciples.

Although the foregoing invention has, for the purposes of clarity andunderstanding, been described in some detail by way of illustration andexample, it will be obvious that certain changes and modifications maybe practiced which will still fall within the scope of the appendedclaims. Moreover, it will be apparent that certain features of eachembodiment as well as features disclosed in each reference incorporatedherein, can be used in combination with devices illustrated in otherembodiments. Accordingly, the above description should be construed asillustrative, and not in a limiting sense, the scope of the inventionbeing defined by the following claims.

What is claimed is:
 1. A variable diameter expansion frame, comprising:an outer wire having a proximal end, a distal end, and a lumentherebetween; an inner wire having a proximal end and a distal end, theinner wire being disposed within the lumen of the outer wire, the innerwire slideable relative to the outer wire; and a substantially circularframe attached at a first circumferential point to the distal end of theouter wire, and attached at a second circumferential point to the distalend of the inner wire, the first circumferential point being disposedapproximately 180° from the second circumferential point, wherein,during use, the outer wire is displaced relative to the inner wire, andthe circular frame is caused to rotate about an axis perpendicular tothe line defined by the first and second circumferential points.
 2. Theexpansion frame of claim 1, wherein the outer wire has a hole throughits wall near the distal end, and wherein the inner wire passes throughthe hole in the outer wire.
 3. The expansion frame of claim 2, furthercomprising a force biasing element disposed about the distal end of theinner wire and biasing the second circumferential point of the circularframe away from the hole of the outer wire.
 4. The expansion frame ofclaim 3, wherein the force biasing element is a spring.
 5. The expansionframe of claim 1, further comprising a filter mesh disposed about thecircular frame.
 6. The expansion frame of claim 1, further comprising animpermeable membrane disposed about the circular frame.
 7. The expansionframe of claim 1, further comprising a syringe having a barrel and aplunger, wherein the proximal end of the inner wire passes through adistal surface of the plunger and is mounted on the barrel.
 8. Theexpansion frame of claim 7, wherein the outer wire is mounted on thedistal surface of the plunger.
 9. The expansion frame of claim 7,further comprising a locking mechanism capable of fixing thedisplacement between the plunger and the barrel.
 10. The expansion frameof claim 1, further comprising an angioplasty catheter adapted toreceive and be guided by the outer wire of the expansion frame.
 11. Theexpansion frame of claim 1, further comprising an stent deploymentcatheter adapted to receive and be guided by the outer wire of theexpansion frame.
 12. The expansion frame of claim 1, further comprisingan atherectomy catheter adapted to receive and be guided by the outerwire of the expansion frame.
 13. The expansion frame of claim 1, furthercomprising an imaging catheter adapted to receive and be guided by theouter wire of the expansion frame.
 14. A method for deploying a medialdevice within a body, comprising the steps of: providing an expansionframe comprising an outer wire, an inner wire, and a substantiallycircular frame attached at a first point to a distal end of the outerwire, and attached at a second point to a distal end of the inner wire,the inner wire being disposed within the lumen of the outer wire, theinner wire slideable relative to the outer wire; introducing theexpansion frame into a lumen within the body of a patient; advancing theexpansion frame to a region of interest; and retracting a proximal endof the outer wire relative to a proximal end of the inner wire, whereinthe circular frame rotates about an axis perpendicular to the linedefined by the first and second point, and the circular frame therebycircumferentially engages the luminal wall.
 15. The method of claim 14,wherein the expansion frame further comprises a filter mesh disposedabout the circular frame.
 16. The method of claim 14, wherein theexpansion frame further comprises an impermeable membrane disposed aboutthe circular frame.
 17. The method of claim 14, wherein the lumen is avessel.
 18. The method of claim 17, wherein the vessel is an artery. 19.An expansion frame system, comprising: a cannula having a proximal end,a distal end, a first lumen therebetween, and a side port communicatingwith a second lumen which extends to the distal end of the cannula; anda variable diameter expansion frame comprising an outer wire having aproximal end and a distal end, an inner wire having a proximal end and adistal end, the inner wire being disposed within the lumen of the outerwire, the inner wire slideable relative to the outer wire, and asubstantially circular frame attached at a first circumferential pointto the distal end of the outer wire, and attached at a secondcircumferential point to the distal end of the inner wire, the firstcircumferential point being disposed approximately 180° from the secondcircumferential point, wherein, during use, the expansion frame isadvanced through the side port of the cannula and is deployed within thelumen of a vessel.
 20. The method of claim 18, wherein the artery is anaorta.
 21. The method of claim 18, wherein the artery is a carotidartery.
 22. The method of claim 14, further comprising the step ofperforming an endoluminal procedure upstream of the expansion frame. 23.The method of claim 22, wherein embolic materials are dislodged duringthe procedure and captured by the expansion frame.
 24. The method ofclaim 14, wherein the expansion frame is introduced through an incisionby direct access.
 25. The method of claim 14, wherein the expansionframe is introduced percutaneously.
 26. The method of claim 14, whereina radiopaque marker is mounted on the circular frame.
 27. The method ofclaim 14, further comprising the step of verifying the position of theframe using fluoroscopy.
 28. The method of claim 22, wherein theendoluminal procedure is performed by advancing an endoluminalinstrument over the outer wire.
 29. The method of claim 28, wherein theendoluminal instrument is an angioplasty catheter adapted to receive andbe guided by the outer wire of the expansion frame.
 30. The method ofclaim 28, wherein the endoluminal instrument is a stent deploymentcatheter adapted to receive and be guided by the outer wire of theexpansion frame.
 31. The method of claim 28, wherein the endoluminalinstrument is an atherectomy catheter adapted to receive and be guidedby the outer wire of the expansion frame.
 32. The method of claim 28,wherein the endoluminal instrument is an imaging catheter adapted toreceive and be guided by the outer wire of the expansion frame.
 33. Themethod of claim 30, wherein the stent deployment catheter comprises: aself-expanding stent disposed about the outer wire; and a sheathdisposed about the stent, wherein the sheath is retracted to release thestent.
 34. The method of claim 17, wherein the step of introducing theexpansion frame into the vessel comprises advancing the expansion framethrough an introducer.
 35. The method of claim 34, wherein theintroducer comprises a cannula.
 36. The method of claim 34, wherein theintroducer is a port on a cannula.
 37. The method of claim 36, whereinthe port is separate from a lumen of the cannula.
 38. The expansionframe of claim 19, wherein during use, the outer wire is displacedrelative to the inner wire and the circular frame is caused to rotateabout an axis perpendicular to the line defined by the first and secondcircumferential points.
 39. The expansion frame of claim 19, wherein thesecond lumen communicates with the first lumen.
 40. The expansion frameof claim 19, wherein the cannula is an arterial cannula.
 41. Theexpansion frame of claim 19, wherein the side port further comprises ahemostatic valve.
 42. The expansion frame of claim 19, wherein thesecond lumen is separate from the first lumen and communicates at adistal end with a port.